Safety door



May 13 1924, 1,493,690

H. A. MARTIN SAFETY DOOR Filed Jan. 20. 1922 INVENTOR.

ATT RNEYS Patented May is, me.

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Application filed January 20, 1922. Serialflo. 530,735.

To a]? 207mm it may concern.

Be it known that I. HENRY A. MARTIN, a citizen of the United States, anda resident of lVashington, District of Columbia, 5 have'invented a newand useful Improvement in Safety Doors, of which the following is aspecification, the principle of the invention being herein explained andthe best mode in which I have contemplated l applying that principle, soas to'distinguish it from other inventions.

The present improvement, relating as indicated to safety doors, havemore particular regard to the provision of locking 1 means for use withrevolving doors for banking rooms. or in like situations where in theevent of attempted robbery, or for other reasons, it may be desired tocontrol the entrance or exit to such rooms from a remote point. Afurther objectis to provide means for automatically giving an alarm incase occasion arises thus to look a door so that the police orguardianof a building may be notified of danger.

2 To the accomplishment of the foregoing and related ends, saidinvention, then, consists of the means hereinafter fully described andparticularlypointed out in the claims, the annexed drawing setting forthin detail certain mechanism'embodying theinvention, such disclosed meansconstituting, however, but one of various mechanical forms in which thetion may be used. In said annexed drawing:

Fig. 1 is a broken central section of a revolving door of the type towhich my present improvements are more particularly applicable, certainof the control connec- 4 tions as well as the alarm system.being showndiagrammatically; and Fig. 2 is a sectionalview of a detail illustratinga modification in construction.

The detailed construction of the revolving door proper forms of courseno partof the present invention and it is not intended to imply that thelatter is limited in its use to a door of this type only, since it maybe employed in connection with any door so designed to swing about avertical axis. In the illustrative door shown there will be a plurality(usually four) of radially proecting sections lsupported to rotate abouta central axis within a suitable door frame principle of the inven- 2.The side portions ofsuch frame are usually of circular conformation incross-section and of suificient depth so that there is at no timeprovided a free opening through the doorway. that will prevent the doorfrom rotating will insure against ingress or egress.

In the preferred construction shown in the drawing the aforesaid locking-means comprise a central shaft 3 about which the door is adapted torotate, as hereinbefore explained, the sections 1 of the doorbeing tothis end attached to a tubular central member 4 journaled upon saidshaft. Roller bearings 5, or like anti-friction means, will usually beinterposedbetween Accordingly, locking means the floor 6 and the lowerend of said tubular member in order to render the door more easilyrotatable, the shaft 3 serving merely to hold the axis of the door inproper vertical position. Said shaft is nonrotatably held butlongitudinally movable within tubular member +1 by being providedpreferably at its upper end, with an enlargement 7 of polygonal, e.g.,square form in cross-section, the opening 8 in the upper portion-ofthe door frame in which such enlarged portion is held being ofcorresponding form. ,There is also provided in the upper end of tubularmember 4 a recess 9 of the same form as such enlargement 7 on the shaft,so that if the latter is dropped below the door frame 2, it will engagewith such recess 9 and thus effectively lock the door against rotation,as will be readily understood.

For normally retaining shaft 3 in raised position a pivotal latch 10 isprovided,such latch engaging a flange 11 on the upper end of the shaftabove the enlarged portion 7. An electro-magnetically actuated catch 21is adapted in turn to engage such latch to prevent same turning aboutits pivot so that with the parts in the position shown in Fig. 1, theshaft 3 is held in its raised position. Energization of the solenoid 12,however, serves to withdraw said catchland thus leave the latch 10 freeto drop' out of the path of the flange '11 so that the shaft 3 will inturn drop under its own weight into locking engagement with tubularmember 4. The electric circuit 13, whereby solenoid 12 may be thisenergized, is controlled by one or more suitable switches ll which, inthe case of a banking iii about such room, thus permitting the door tobe locked instantly by any of the tellers or other employees in thebank. To reset the locking mechanism and permit the door again tobe-rotated, it is merely necessary to lift theshaft 3, but accessthereto can besafe-guarded so that this will only be pos sible by anauthorized person.

For the purpose of giving" an extraneous alarm, a: switch 15 is locatedat a point heneath "the lower end of shaft 3 or inconnection with theflange 11 on the upper end thereof so that downward movement of suchshaft will close such switch and thus ring a hell or actuate any othersuitable electro-magnetic device for giving such alarm.

In order to insure ready engagement of the enlarged portion of the shaft3 withthe recess in the tubular member 2, such enlarged portion 16 maybe made of the truncated pyramidal form shown in Fig. 2, instead of thestraight polygonal cross-section shown in Fig. l, and the recess 1? insaid member of correspondingly tapered form. Accordingly the shaft willbe free to drop as soon as latch 10 is released irrespective of whetherthe recess is strictly in register with such enlarged portion or not andthe ter will automatically find itself upon partial rotationor the door.

uch partial rotation, however, will not be sufiicient to permit a personto pass through the doorway.

Uther modes of a olyin the principle oi? my invention he employedinstead of the one explained, change being made as regards the mechanismherein disclosed,

' provided the means by any the following claims or the equivalent ofsuch stated means be employed.

said shaft against such movement, roe

re eases I therefore particularly point out and distinctly claim as myinvention 1. The combination with a door or like closure designed toswing about a vertical axis, of a shaft about which said door thusswings, said shaft beingnon-rotatably held but longitudinally movableinto locking eugagement with said door, means normally retaining said,shaft out of such engaging position, and signal'means adapted to beactuated upon movement of said shaft into such en aging position.

2 The combination 'With a revolving door having a central tubular membersupported upon independent bearings, of a central shaft about which saidtubular member revolves, said shaft being nonrotatably held butlongitudinally movable, a recess of polygonal cross section in saidcentral tubular member, and an enlargement of corresponding crosssection in said shaft adapt ed to engage such recess upon downwardmovement of said-shaft, and a catch nor mally retaining said shaftagainst such movement.

8. The combination with a. revolving door, of a central shaft aboutwhich said door thus revolves, said being non-. rotatably held butlongitudinally movable, a recess of polygonal cross section in saiddoor, and enlargement of? corresponding cross section in said shaftadapted gage such recess upon downward movement of said shaft, a catchnormally retaini' s controlled "from a point from.

door adapted to release said catch, 1

circuit, and a switch controlling said. cin cult and adapted to beactuated upon merit of said shaft. d F r ,c Qigne by me ens lo day or as1922.

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